How do you fancy spitting into a tube and finding out about your genes? You can buy one online now and get details of your ancestry, carrier status of various inherited diseases, risk of common conditions and random wacky facts such as whether you’re likely to develop male-pattern baldness. Not bad for £124.99 from Superdrug.

The kit is called 23andme and its co-founder and chief executive is Anne Wojcicki. While 23andme has been able to offer the tests in the UK and Canada, it had run-ins with the US Food and Drug Administration (FDA) over its concerns about the accuracy of data collected. In 2013 the FDA banned the company from selling tests directly to consumers.

The company has since relaunched a scaled back version and is the first and only direct-to-consumer genetic test available to individuals in the US that includes reports that meet FDA standards. Its US tests give information on carrier status, ancestry, wellness and trait reports but don’t include the information on drug response and genetic risk factors that are included in the UK test, according to the company.

Consumer-powered healthcare?

“Direct-to-consumer healthcare is coming,” said Wojcicki at Fortune’s Most Powerful Women Next Gen conference last month . “Do you have to go to your physician for everything? Do you have to go for a blood test? Do you have to go for all your genetic information?”

The answer to these questions is clearly “no”. It was easier for me to go online and get a kit than to get an appointment with my local GP. I spat into the device, put the kit in the post and await my results with some curiosity, a pinch of scepticism and an unexpected degree of anxiety.

23andme doesn’t test the whole genome. It identifies genetic markers known as single-nucleotide polymorphisms (SNPs), or “snips”. SNPs are positions along the DNA chain where genetic variations commonly occur.

Fans of self-testing says it’s interesting to find out about your ancestry, useful to know if you’re at increased risk of certain conditions and reassuring to know if you’re not. If the test points to risk, you can take preventive action, for example by losing weight if you’re prone to diabetes. You may be more likely to take part in a national screening programme such as the NHS bowel cancer screening programme if the test shows an increased risk of bowel cancer.

Erynn Gordon, director of clinical development at 23andme, says screening programmes that target specific communities (like sickle-cell anaemia among African-Caribbean people) may miss other individuals who are at risk. “The narrow approach to screening doesn’t take into account our diverse communities.” She also points to a (very small) study that suggests that people who receive unexpected information about carrier status don’t suffer undue anxiety as well as research that concludes people understand the implications of testing very well.

Limitations

The test is controversial and the cons are important. Consultant genetics counsellor Christine Patch says she has several areas of concern about self-testing: people failing to understand the limitations of the test; what the data will be used for and who will have access to it; and the implications for cash-strapped health services in terms of inappropriate requests for follow-up testing.

Once you have information about your genetic risk, for example, do you have to declare it to an insurance company? Do you have an ethical duty to tell other family members? Does the NHS have to pay for further testing?

“You may find you’re at increased risk of Alzheimer’s disease … and there’s nothing [specific] you can do about it,” says Patch. Most common diseases, like asthma, high blood pressure and diabetes, are a complex mix of genetic and environmental factors. And some inherited conditions like being a carrier of cystic fibrosis, may result from many different abnormalities not detected by the kit. The kit may offer false reassurance, she says.

There are already various free online tools to estimate your individual risk of getting a condition like osteoporosis, a heart attack or stroke, or diabetes. And people with a family history of serious conditions like Huntington’s Chorea need expert genetic counselling to work out risk and reproductive options.

Dr Katherine Leask, a medico-legal adviser with the Medical Defence Union, says doctors need to be aware of the challenges that increased use of kits like 23andme will pose. “Genomic medicine is going to become more mainstream and doctors need to know what tests are available. If someone needs genetic testing because of their family history … then doctors need to consider whether tests need to be offered.” Chances are this will involve referral to a specialist centre that can offer counselling and specific testing if appropriate rather than telling them to buy a kit.

The Department of Health is running a hugely ambitious programme through its company Genomics England. It aims to sequence 100,000 whole genomes from 70,000 people who have either common cancers or rare inherited diseases, together with their families. Their claims are notably more modest than the direct-to-consumer marketing. “Doing this [genome sequencing] may help medical teams provide better diagnosis or treatment. But it may not because not enough is known yet about the meaning of all the genomic data.” says communications manager Lisa Dinh.

There are no plans to roll out genome testing on the NHS for the entire population, says Dinh. “However it is likely that our knowledge about the genome will expand in coming years, which should mean better and quicker diagnoses and treatments for more patients. We do not have an official view on 23andMe.”.

Patch says: “I’m not against the kits; if people want to spend their money on it, that’s fine. But personally, I wouldn’t do the test. I do my best to stay healthy, and if I become unwell I’ll get help. But I’m not going to go looking for problems.”